OVERALL OBJECTIVE: This study will explore how characteristics of the health care facility affect the delivery of care. SPECIFIC AIM: Specifically, the study will examine how pre-operative ophthalmic diagnostic testing for cataract extraction is affected by type of facility (ambulatory surgical center, office, or hospital outpatient department), organization size (measured by number of employees), and profit status. RESEARCH DESIGN AND METHODS: This study involves a cross-sectional analysis of roughly 30,000 cataract patients from a five percent sample of Medicare Part B claims data. Using univariate, bivariate, and multivariate statistics the number, type, and estimated costs (using RBRVS) of pre-operative ophthalmic diagnostic tests performed during a 42- day window before cataract extractions will be examined, and the effect of health care facility characteristics on pre-operative cataract management will be investigated. SIGNIFICANCE AND HEALTH RELATEDNESS: Quality of care in cataract management and appropriate reimbursement policy are particularly important health issues to the federal government, since the procedure is the most commonly performed procedure for Medicare beneficiaries, and is the largest single Medicare biller. Previous studies have identified the extensive variation that exists in all aspects - pre-, intra-, and post-operative - of cataract management. Further, recent research and current national guidelines for cataract management call into question the clinical usefulness of several common pre-operative ophthalmic diagnostic tests. Finally, health services researchers have shown a long-standing interest in aspects of the health care facility, and have found associations between both patterns of care and costs with certain facility characteristics. This study will further this type of research by examining three key aspects of the health care facility. Findings from this study will help identify the extent that these facility characteristics are associated with different types and amounts of diagnostic testing. This information should be significant for understanding patterns of cataract management, for implementing practice guidelines for cataract management, and for formulating reimbursement policy for different sites of care.